Klobuchar was the first Democrat to enter the race after the unexpected retirement of her fellow Democrat, Sen. Mark Dayton. Her energetic campaign and formidable fundraising chased three other prominent Democrats out of the race before the primary, leaving her room to fire away for months on Kennedy's support for Bush administration policies and ties to congressional leadership in Washington.

Kennedy's loss sidetracks the political career of a one-time rising star who months ago was seen as his party's best chance to pick up a Senate seat. With her win, Klobuchar becomes the first woman that Minnesotans have elected U.S. senator. Muriel Humphrey, the widow of Vice President Hubert Humphrey, was appointed to finish his final Senate term after his death in 1978, serving 11 months.

Voters indicated Kennedy's vocal support of a continued strong U.S. military presence in Iraq likely cost him support.

"We should've never been in Iraq in the first place," said Jim Robinson, a nonprofit program director from Circle Pines.

Mark Gobran, 43, a banker from Lino Lakes, said he was disenchanted with both the war and the direction of Congress. Klobuchar and Democrats worked throughout the campaign to weigh down Kennedy for being an incumbent Republican congressman.

"I don't agree with what's been happening in Congress over the last eight years or so," said Gobran, who identified himself as a Democratic-leaning independent. "The war in Iraq is probably 85 percent of the issue."